Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Rubidium and caesium
19 practice questions
Practice questions
1–8 of 8 · Normal
Question 1
2 marks · Normal
Answer and see the solution →State two physical properties that are characteristic of lithium, sodium, and potassium.
Question 2
4 marks · Normal
Answer and see the solution →(a)[1 mark]Write a word equation for the reaction of sodium with water.
(b)[2 marks]Describe two visible observations when a small piece of potassium is added to water.
(c)[1 mark]Give the names of the two products formed in the reaction between potassium and water.
Question 3
3 marks · Normal
Answer and see the solution →A student is given the information below about the reactions of three Group 1 metals with water:
Metal Time taken to disappear in water (s) Lithium 45 Sodium 35 Potassium 18 Calculate the average decrease in time taken to disappear from lithium to potassium per step down the group.
Question 4
3 marks · Normal
Answer and see the solution →Explain, in terms of atomic structure, why potassium is more reactive than lithium.
Question 5
4 marks · Normal
Answer and see the solution →The table below shows times taken for different alkali metals to disappear when added to water:
Time taken to disappear in water Metal Time (s) Lithium 50 Sodium 30 Potassium 11 (a)[1 mark]State the relationship between the metal and the time taken to disappear in water.
(b)[2 marks]Which metal is the most reactive? Explain how the data supports your answer.
(c)[1 mark]Rubidium is below potassium in Group 1. Predict what you would expect to observe if rubidium was added to water.
Question 6
1 mark · Normal
Answer and check →Which statement best explains the trend in reactivity of Group 1 metals as you go down the group?
- A.The outer electron is closer to the nucleus and more difficult to remove.
- B.Metals lower in the group have smaller atoms.
- C.The outer electron is further from the nucleus and less strongly attracted.
- D.The number of protons decreases down the group.
Question 7
2 marks · Normal
Answer and see the solution →Lithium, sodium, and potassium all react with water. State the name and a property of the gas produced in each reaction.
Question 8
4 marks · Normal
Answer and see the solution →(a)[1 mark]Write a balanced chemical equation for the reaction of potassium with water.
(b)[2 marks]Describe what you would observe when a small piece of sodium is placed in water.
(c)[1 mark]Suggest one safety precaution that should be taken when carrying out this reaction.